The present invention relates to a device for holding a plurality of baldes such as might be used for crimping a moving multilayer paper web at a plurality of locations along its length. Such a holder is particularly useful in machines for collating several paper webs, such as might be done in the manufacture of business forms.
Multilayer, preprinted business forms are commonly used, for instance, where it is desired to make multiple copies of a document at the same time. In manufacturing such forms, a single layer web is printed for each layer of the form, and the individual webs are then supplied to a collator for proper arrangement into layers. Normally, after collating, a perforation is provided across the webs at a plurality of predetermined locations, so that individual forms may be separated from the web for use. The individual forms typically are not separated until immediately before or after use, and the forms are packaged for shipment and/or storage by folding the web in accordion-like fashion along the perforations.
In order to keep the various layers of the form together until such time as it is desired to separate them, it is common to provide a plurality of crimps along each edge of the multilayer web during collating. The crimping is normally performed by a series of crimp blades, each of which has a plurality of fingers for cooperating with grooves provided in an anvil surface. The fingers puncture and pass through the web into the grooves of the anvil surface, thereby providing a plurality of slots through the layers of the web. The crimp blades are designed, however, such that the small portions of the paper layers originally located where the slots are formed are not severed from the web, but rather pushed downwardly through the slot formed in the underlying layers. These small portions of paper thus serve to hold the various layers together.
The crimp blades are usually mounted to one or more blade holders which in turn are mounted to a rotatable shaft. The multilayer web is passed between the blade holders and the cooperating anvil surfaces, and the blade holder shaft is rotated at a speed such that the fingers of the crimp blades and the web approach each other at the same linear speed. Thus, as the web is passed by the blade holders, the blades crimp the web in a pattern predetermined by the arrangement of the blades along the holders.
In addition to the perforations provided across the multilayer web, and the crimping provided along the edges of the web, the web is further provided with a series of holes along the edges of the web. These holes may be used for advancing the web, both during manufacture of the forms, and during their use, for instance, where the individual forms are prepared by a computer printout. Typically, the holes are disposed along the edge of the web at a spacing of 0.50 inch (1.27 cm) center-to-center, and equipment used with forms has been designed to be compatible with such spacing.
Thus, the crimps to be effective must be located along the web so as to avoid the holes. Accordingly, as can be seen in FIG. 1, the crimps are typically centered 0.25 inch (0.635 cm) from the centers of adjacent holes, and are thereby separated from other crimps by an integer number of half-inches.
The perforations separating successive forms represent yet another constraint on the location of the crimps. The perforations must also be located so as not to fall on the holes, and thus, as seen in FIG. 1, are also located 0.25 inch (0.635 cm) from the centers of adjacent holes. It is not desirable, however, for the crimps to fall along a perforation. In such a case, the crimps could begin premature, partial separation of individual forms along the perforation, thereby making accidental full separation much more likely. Moreover, the crimps prevent even, neat folding along the perforations, interfering with the proper arrangement of the web for storage and/or shipping.
The separation between consecutive perforations along the web is, of course, determined by the desired length for the form. In the United States, the two most common lengths for forms are 81/2 inches (21.6 cm) and 11 inches (27.9 cm), and in Europe, the most common lengths are 81/2 inches (21.6 cm) and 12 inches (30.5 cm). In the case of 11-inch and 12-inch forms, as well as any other form of a length of an integer number of inches, it can be seen that consecutive perforations are separated by an even number of half-inch intervals. The crimp blades can therefore be arranged to provide crimps in intervals of an even number of half-inches. By separating the initial crimp from the initial perforation by an odd number of half-inch intervals, the perforations and crimps will not coincide.
This approach is not usable in the case of 81/2 inch forms. Since the perforations are separated by an odd number of half-inch intervals, a separation of an even number of intervals between crimps would result in at least some perforations coinciding with a crimp. Thus, it can be seen that a particular arrangement of crimp blades that is suitable for use with 11-inch forms is not usable with 81/2 inch forms, and vice versa.
Typically, the problem of crimp spacing for different sizes of forms is solved by providing two different crimp blade holders, one size for each of the different forms. When the collator is to be readied for changing from one size form to another, the blade holders mounted to the rotatable shaft must be disassembled and removed from the shaft, and a new set of blade holders providing a different spacing must be installed. This represents a relatively time-consuming process, and requires the operator of the collator to keep two sets of crimp blade holders on hand.
What is needed, therefore, is a single set of crimp blade holders that are capable of use with either 81/2 or 11 inch forms. Such holders should be capable of arranging crimp blades such that in either case, crimps do not coincide with perforations along the multilayer web. Further, preparing the crimp blade holders for use with one size of form following use with another size form should be relatively quick and simple to perform.